Method of cleaning checkerwork



Nov. 8, 1938.

F. H. I OFTUs 2,136,113

METHOD oF CLEANING cHEcKEnwoRK Filed Deo. l5, 1956 2 Sheets-Sheet 1Prg-.1.

6MM/Wam ATTORNEYS Nov. 8, 1938. F. H. Lor-Tus 2,136,113

METHOD OF CLEANING CHECKERWORK Filed Dec. 15, 1936 2 Sheets-Sheet 2INVENTOR ,jm/. XW BYaAM//m A'ITCRNEYS Patented Nov. 1938- UNITED STATESPATENT NOFFICE 2 Claims.

My invention relates to regenerative furnaces,

and more particularly to the operation of the regenerators of suchfurnaces. In exemplary way, I shall consider the invention as it isprac-- 5 ticed in glass furnaces.

The usual glass furnace includes two regenerators arranged at theopposite sides of the furnace chamber. The air for sustaining combustionwithin the furnace is led through and heated by the hot checkerwork inone regenerator, while the hot waste gases of the furnace are passedthrough and heat the checkerwork in the other regenerator. In known waythe hot waste gases ontheir way through the furnace chamber entrainvapors and particles of dust and molten material, and, as the gases passfrom the furnace into the regenerator, the included vapors condense.Substantial quantities of the condensate and other particulate materialincluded in the streaming gases are precipitated upon the surl faces ofthe checkerwork within the regenerator.

During normal furnace operation, this precipitated material accumulatesand becomes incrusted upon the surfaces of the checkerwork, g5 and. asthe furnace continues in operation, the ,accumulations increase in size,until ultimately the passageways in the checkerwork become soconstricted and clogged as to inhibit efficient operation.

Moreparticularly, my invention concerns the removal of accumulatedmaterial from the checkerwork of a regenerator, and consists in methodto such end.

In the accompanying drawings a regenerator, in the course of beingcleansed in accordance with my invention, is illustrated partly in sideelevation and partly in vertical section. Fig. II is a sectional view ofthe regenerator, taken on the plane II-II of Fig. I; the body ofcheckerwork within the regenerator is shown fragmentarily and invertical section. Fig. III is a fragmentary, diagrammatic view in planof the two regenerators of a glass furnace, illustrating the apparatusof the invention in use. And Fig. IV is a fragmentary view, in sideelevation and to larger scale, of an instrument in which and in theoperation of which the invention is realized. Referring to Figs. I andII of the drawings, a regenerator I of known sort is illustrated. Thewalls and arched roof of the regenerator are constructed of refractorymasonry, and within the chamber dened by such walls and roof a body ofcheckerwork C is provided. The checkerwork consistsof a plurality ofvertical walls W that are spaced apart transversely of the regeneratorand extendk in parallelism longitudinally thereof. The

' walls Ware builtof refractory tiles lt, and are e interconnectedbyrefractory checlrex'fblocks b. 'I'he blocks b lie in verticallyspaced-"apart r horizontal courses h, and in the severalcourses theblocks are vertically staggered, as illustrated in Fig. I. A morecomplete description of the checkerwork will be found in Patent No.1,686,826, granted to me on October 9, 1928.

In the end-wall 2 of the regenerator, several horizontal lines ofrefractory blocks 3' are embodied. 'I'he blocks 3 are of specializedstructure, including conical passages 4 that normally are closed, bymeans of refractory plugs. 5 (Fig. I). The blocks are so positioned inthe end-wall 2 that their passages 4 are severally directed into certainof the channels defined by and between 4the vertical walls W and thehorizontal courses h of the blocks b of the checkerwork. As the drawingsindicate, I do not provide a line of blocks I for each horizontal courseh. of blocks b in the checkerwork, and in this case I so arrange theseveral lines of blocks 3 that passages I are aligned with the channelsbetween the first and second, fourth and fth, and seventh and eighth,etc., courses h ofthe checker-blocks b.

The apparatus by means of which I practice'my invention consists in ahollow, Aflexible lance L provided with a perforate head. 'Ihe hollowshaft of the lance, otherwise closed, is provided with an inlet which inservice is connected to a supply of steam, air, or other suitable fluidunder high pressure, whereby violent jets of the compressed fluid may becaused to flow from the lance head.

Referring to Fig. IV, the body of the lance L consists in a shaft ofsteel tubing 6 of relatively great rigidity, embodying at one or morepoints (in this case at two points) in its extent a length 'I of metaltubing of relative great flexibility. The shaft ofthe lance may be saidto comprise a plurality of rigid tubes that are flexibly interconnected.In this case each section of flexible tubing 'I comprises metal hose ofknown sort, 1" in diameterandlS in length, while the several sections ofrigid tubing 6 comprise 1" steel pipe, of such length as to afford inthe assembly `a lance of desired reach. Couplings 6 secure ,the tubingsections in assembly. The head or nozzle 9 of the lance, secured by aunion I0 to the foremost section of rigid tubing 6, includes fiveoriceso, one directed axially of the lance, and the others inclined thereto,as shown. 'I'he tail-end of the lance is secured in a hollow Y fittingIl; one leg of the Y is closed by a short solid rod I2, equipped with ahandle-bar I3 extending transversely through the rod I2 and covered witha jacket I4 of heat-insulating material, and the other leg of the Y isconnected,V

through a valve I5,-with the end of a flexible metallic hose I6. y

Inv Fig. III two regenerators i and lll are diagrammatically illustratedin plan. The furnace with which the regenerators are arranged is notshown,.but the usual waste gas passages i1,

running below iioor level from the regenerators to the furnace stack I8,are shown in dotted lines. together lwith the usual air inlets I9 andreversing valves 20.

A steam supply line 2| is run from. a boiler (not shown) into the regionor space between the stack I8 and the end-walls 2 of the regenerators I,|00, it being understood that it is into this region or space thatworkmen enter, while the furnace is in operation, to operate thereversing valves and practice the method of this invention.

In the majority of cases the space available to workmen behind theregenerators is small, and, as will presently appear, the flexiblestructure of my lance lends itself to ready operation in such crampedquarters.

When it is desired to clean the checkerwork in the regenerators I and|00, my lance L is by dexible hose I6 and a feed line 22 connected tothe steam line 2|; indeed, a second lance LL may also be connected tothe steam line, as shown in Fig. III. The valve I5 of each lance isclosed, and steam is supplied to the line 2| under 125 pounds pressure.When the connections have been completed, the attendant removes the plug5 (Fig. I) from one of the openings l in the upper line of blocks 3 inthe\endwall of the regenerator he is about to clean. Into the uncoveredopening he projects the head-end of the lance, as indicated in theregenerator I in Fig. III, and it will be observed that the shaft of thelance may be flexed or bowed. readily to admit of this operation in thecramped working quarters, alluded to above. Then, by means of ahand-lever 23 (Fig. IV), he opens the valve I5, and charges the hollowshaft of the lance with steam under pounds feed-line pressure.Immediately violent jets of steam shoot from the orifices o0 in lancehead nozzle 9. The lance is moved inward, and the head of the lance isprojected into the body of checkerwork in the regenerator, that is sosay,

into a particular one of the horizontal channels formed by and betweentwo of the walls W and two adjacent courses h of blocks b of thecheckerwork. The violent jets of steam crack and blast away the dust andincrusted accumulations from the surfaces of the checkerwork tiles t andblocks b that border the channel into which the lance is moved, and thefragmented and detached material falls to the bottom of the regenerator,whence it may be readily removed in known way. The lance is reciprocatedand rotated several times in the channel, the handle-bar I3 facilitating the manipulation, and then the valve I5 is closed, the lance iswithdrawn, and the plug 5 is restored to position in the opening in thewall 2. The operation is repeated for each opening 4 in the top line ofblocks 3 in the end-wall 2 of the regenerator (cf. Fig. II), then in thenext lower line of blocks 3, and so on, until the lance has beenoperated in each of the checkerwork channels into which access may behad by way of the openings l in blocks 3. Thus, the checker? work C isprogressively cleaned from the top downward, and the detached materialfalling to the floor of the regenerator, is removed in usual way.

In the foregoing specification, it will be noted that in service thelance is snaked through the end-wall of the regenerator, and, chargedwith uid (steam, in this case) under high pressure,

is advanced in a horizontal channel through the checkerwork of theregenerator. The arrangement of the nozzles or orifices o in the lanceis important. One orifice directs a jet a of steam in the line ofadvance of the lance, and the other orifices direct four jets dangulariy to such line of advance, two o1' the jets d extendingangularly forward with respect to the nozzle and two rearward, as shownin Fig. I. Ihe angularly directed jets d are effective not only upon thetiles t and blocks b that immediately define the channel into which thelance is projected but upon all tiles and blocks in the vicinity of suchchannel. That is to say, the jets d play diagonally into several coursesof blocks b, both above and below the line of advance of the lance head9, as may be visualized in Fig. I. 'I'hus it is that the operation ofthe lance in a channel formed by and between two vertical walls of tileand two horizontal courses of blocks is, advantageously, effective toclean the surfaces of the tile and blocks not only in such channel, butin the channels immediately above and below.

I claim as my invention:

l. In the operation of a regenerator that comprises a refractory walledchamber including a body of checkerwork formed of a plurality ofparallel, spaced-apart, vertical walls of refractory tile interconnectedby transversely extending refractory blocks, with such blocks arrangedin vertically spaced-apart horizontal courses and with the blocks in onecourse staggered with respect to the blocks in adjacent courses; theherein described method which consists in introducing a lancehorizontally through the refractory end wall of said chamber into ahorizontal channel formed by and between two of said vertical* walls oftile and two adjacent horizontal courses of transverse blocks, advancingand turning the lance while causing jets of fluid to flow violently fromthe leading end of the lance in direction extending angularly to boththe vertical and the horizontal, and thereby blasting away accumulationsfrom the surfaces of the tile and block in said channel and from thesurfaces of the tile and blocks that form horizontal channels above andbelow said channel.

2. In the operation of a regenerator that comprises a refractory walledchamber including a body of checkerwork formed in a plurality ofparallel, spaced-apart, vertical walls of refractory tile interconnectedby transversely extending refractory blocks, with such blocks arrangedin vertically spaced-apart horizontal courses and with the blocks in onecourse staggered with respect to the blocks in adjacent courses; theherein described method which consists in introducing a lancehorizontally through the refractory end wall of said chamber into ahorizontal channel formed by and between two lof said vertical walls oftile and two adjacent horizontal courses of transverse blocks, advancingand turning the lance while causing .fluid to iiow violently from theleading 'end of said lance in jets extending angularly, two forward andtwo rearward, of the direction of advance, and thereby blasting awayaccumulations from the surfaces of the tile and blocks in said channeland from the surfaces of the tile and blocks that form horizontalchannels above and below said channel.

FRED H. LOFTUS.

